Ultrasonic measurements for assessing the elastic parameters of two-component grout used in full-face mechanized tunnelling

The use of shield machines and instantaneous segment linings for tunnel construction is one of the most used tunnelling methods today. Despite a large number of applications in different tunnelling projects all around the world, knowledge of the behaviour of two-component grout is quite limited, mainly due to the fast hardening process that inhibits using the classic approach for concrete characterization. In the present work, an innovative approach based on ultrasonic measurements is introduced, aimed to characterize the elastic properties of this innovative backfilling material. Specifically, ultrasonic pulse velocity was applied to two-component grout samples to describe the interesting and fast evolution of the material from the mixing phase until 6 months of curing using geophysics parameters. The dynamic Young’s modulus (E) and the dynamic shear modulus (G) exhibited a clear increasing trend, starting from values of a few tens of MPa to final values equal to 1000 MPa and 340 MPa, respectively. The Poisson’s ratio (ν), close to the value of incompressible materials (0.5) at the short curing time, exhibited a decreasing trend, reaching roughly 0.445 after 3 months of curing

Detection of Obfuscation Techniques in Android Applications

Current signature detection mechanisms can be easily evaded by malware writers by applying obfuscation techniques. Employing morphing code techniques, attackers are able to generate several variants of one malicious sample, making the corresponding signature obsolete. Considering that the signature definition is a laborious process manually performed by security analysts, in this paper we propose a method, exploiting static analysis and Machine Learning classification algorithms, to identify whether a mobile application is modified by means of one or more morphing techniques. We perform experiments on a real-world dataset of Android applications (morphed and original), obtaining encouraging results in the obfuscation technique(s) identification

PiCo: High-performance data analytics pipelines in modern C++

In this paper, we present a new C++ API with a fluent interface called PiCo (Pipeline Composition). PiCo’s programming model aims at making easier the programming of data analytics applications while preserving or enhancing their performance. This is attained through three key design choices: 1) unifying batch and stream data access models, 2) decoupling processing from data layout, and 3) exploiting a stream-oriented, scalable, efficient C++11 runtime system. PiCo proposes a programming model based on pipelines and operators that are polymorphic with respect to data types in the sense that it is possible to reuse the same algorithms and pipelines on different data models (e.g., streams, lists, sets, etc.). Preliminary results show that PiCo, when compared to Spark and Flink, can attain better performances in terms of execution times and can hugely improve memory utilization, both for batch and stream processing.Author's copy (postprint) of C. Misale, M. Drocco, G. Tremblay, A.R. Martinelli, M. Aldinucci, PiCo: High-performance data analytics pipelines in modern C++, Future Generation Computer Systems (2018), https://doi.org/10.1016/j.future.2018.05.03

Unimolecular nucleophilic substitution (S N 1): Structural reactivity evidenced by colored acid-base indicators

The different reactivities between 1°, 2°, and 3° butyl chlorides by the unimolecular nucleophilic substitution (S N 1) mechanism were easily observed at 60 °C by a solvolysis reaction in ethanol with ether formation. The hydrogen ion from the byproduct HCl reacted with an acid-base indicator such as methyl red to induce a color change. At room temperature, the addition of AgNO 3 was used to detect the released chloride ion by AgCl precipitation. The reactivity order (3° > 2° ≫1°) was visually confirmed by both a color change in an indicator and precipitate formation by these safe, quick, and easy assays.Fil: Castro Godoy, Willber David. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Argüello, Juan Elias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; ArgentinaFil: Martinelli, Marisa. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Caminos, Daniel Alberto. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentin

Improved relationship between left and right ventricular electrical activation after cardiac resynchronization therapy in heart failure patients can be quantified by body surface potential mapping

OBJECTIVES: Few studies have evaluated cardiac electrical activation dynamics after cardiac resynchronization therapy. Although this procedure reduces morbidity and mortality in heart failure patients, many approaches attempting to identify the responders have shown that 30% of patients do not attain clinical or functional improvement. This study sought to quantify and characterize the effect of resynchronization therapy on the ventricular electrical activation of patients using body surface potential mapping, a noninvasive tool. METHODS: This retrospective study included 91 resynchronization patients with a mean age of 61 years, left ventricle ejection fraction of 28%, mean QRS duration of 182 ms, and functional class III/IV (78%/22%); the patients underwent 87-lead body surface mapping with the resynchronization device on and off. Thirty-six patients were excluded. Body surface isochronal maps produced 87 maximal/mean global ventricular activation times with three regions identified. The regional activation times for right and left ventricles and their inter-regional right-to-left ventricle gradients were calculated from these results and analyzed. The Mann-Whitney U-test and Kruskall-Wallis test were used for comparisons, with the level of significance set at p≤0.05. RESULTS: During intrinsic rhythms, regional ventricular activation times were significantly different (54.5 ms vs. 95.9 ms in the right and left ventricle regions, respectively). Regarding cardiac resynchronization, the maximal global value was significantly reduced (138 ms to 131 ms), and a downward variation of 19.4% in regional-left and an upward variation of 44.8% in regional-right ventricular activation times resulted in a significantly reduced inter-regional gradient (43.8 ms to 17 ms). CONCLUSIONS: Body surface potential mapping in resynchronization patients yielded electrical ventricular activation times for two cardiac regions with significantly decreased global and regional-left values but significantly increased regional-right values, thus showing an attenuated inter-regional gradient after the cardiac resynchronization therapy

Morphocultural characterization of Alternaria species-groups asociated to wheat diseases in Argentina

Se caracterizaron 40 aislamientos de Alternaria procedentes de trigo, en grupos de morfo-especies en base a sus modelos de esporulación, morfología del conidio/conidióforo, color de la colonia sobre medios específicos (agar DRYES), patogenicidad y producción de toxinas. Se determinaron cuatro grupos-especie de Alternaria involucrados en patologías del trigo: A. alternata, A. arborescens, A. infectoria y A. tenuissima. La caracterización morfológica fue corroborada por comparación con cepas patrones standard de colecciones internacionales (Biopure Referenz Substeranzen GmbH, Tulln, Austria y HebIMI, Inglaterra). El análisis molecular de los aislamientos (extracción de DNA y secuenciación de la región ITS) corroboró la determinación morfocultural. La patogenicidad de los aislamientos se demostró por la producción de síntomas necróticos tales como manchas y atizonamiento foliar, manchado de granos, necrosis radicular y debilitamiento de las plántulas emergidas de granos inoculados. Cada grupo-especie se asoció a la producción de un síntoma o grupo de síntomas determinado siendo el grupo infectoria el más virulento respecto al resto de los grupos analizados. Las toxinas determinadas indican el riesgo micotoxicológico de estas cepas para la salud humana y animal ante el consumo de productos o subproductos que contengan dichos metabolitos. Su falta de regulación en alimentos en Argentina y en otras regiones del mundo es llamativa. A. arborescens se registra por primera vez en asociación a trigo para Argentina.Forty isolates of Alternaria from wheat plants were characterized into species-group considering the sporulation pattern, morphology of conidia, patogenicity and toxins production. For identification PCA media was used and the isolates were classified according the sporulation pattern, morphology of conidia/conidiophores and according the colony colour on DRYES medium. Four species-groups of Alternaria were determined, A. alternata, A. arborescens, A. infectoria, and A. tenuissima groups. This is the first report of A. arborescens on wheat in Argentina. Morphocultural identification was corroborated by molecular analysis PCR- ITS and comparison of isolates with standard strains belonging to international culture collections. Inoculations on wheat grains showed the patogenicity of isolates and symptoms of discoloration, blight and spots on leaves, radicular necrosis and weakness of emerged plants. Wheat cultivars showed different response to the infection according each particular isolate inoculated. In general a correlation between each species-group and each kind of symptom could been shown. The infectoria group has the most virulent strains that induce the highest severity on all tested cultivars. Toxins production highlight the micotoxicologic risk associated to this fungi considering they play a rol in pathogenesis and no current regulations exists in Argentina or in the rest of the world. A. arborescens is registered by first time associated to wheat plants in Argentina.Fil: Perello, Analia Edith. Universidad Nacional de la Plata. Facultad de Ciencias Agrarias y Forestales. Departamento de Ciencias Biológicas. Centro de Investigaciones de Fitopatología. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigaciones de Fitopatología; ArgentinaFil: Aulicino, Mónica Beatriz. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Instituto Fitotécnico de "Santa Catalina"; ArgentinaFil: Martinelli, Clara. Universidad Nacional de la Plata. Facultad de Ciencias Agrarias y Forestales. Departamento de Ciencias Biológicas. Centro de Investigaciones de Fitopatología. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigaciones de Fitopatología; ArgentinaFil: Regueira, Melina. Universidad Nacional de la Plata. Facultad de Ciencias Agrarias y Forestales. Departamento de Ciencias Biológicas. Centro de Investigaciones de Fitopatología. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigaciones de Fitopatología; ArgentinaFil: Moreno, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biología Funcional y Biotecnología; ArgentinaFil: Stenglein, Sebastian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biologia Funcional y Biotecnología; Argentin

Biological Monitoring of Metal Ions Released from Hip Prostheses

The aim of this study was to evaluate the levels of As, Be, Bi, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Se, Tl, V, and Zn, by inductively coupled plasma-mass spectrometry (ICP-MS) in the urine of two groups of patients with two different types of metal-on-metal (MoM) total hip prostheses (ASR DePuy\uae, group A, 25 patients; total Met-Met System Lima\uae, group B, 28 patients). The determination of metals reflected a steady-state release (group A: 9 years after surgery and group B: 6 years after surgery). The results obtained confirmed the increase of Co and Cr urinary levels in both group when compared with the reference values for the general population adopted by the Italian Society of Reference Values (SIVR). In particular, Co and Cr levels exceeded the threshold values in urine, respectively, of 30 \u3bcg and 21 \ub5g, adjusted to creatinine based on the threshold in whole blood of 7 \u3bcg/L proposed by the Medicines and Healthcare Products Regulatory Agency (MHRA). Regarding the other investigated metals, significantly higher values were found in Group A than in Group B. These differences could be due to the type of hip prosthesis implanted, the longer period of time since the implantation, as well as many other factors such as diet, age, drug consumption, physical activity, or presence of dental fillings. The continuous monitoring over the years of metal concentrations in patients carrying a prosthesis could be useful to better identify the sources of these metals